Doorknob keyhole guard



July 29, 1969 Cv. H. BARBER DooRKNoB KEYHOLE GUARD Filed Oct. 5. 1967 Char/es H. Barber INVINTOR,

United States Patent O 3,457,743 DOQRKNB KEYHOLE GUARD Charles H. Barber, P.0. Box 2381, Stateline, Nev. 89449 Filed Oct. S, 1967, Ser. No. 673,042 Int. Cl. EOSb 17/14 U.S. Cl. 70--424 4 Claims ABSTRACT OF THE DISCLOSURE A keyhole guard plate is fashioned into a shield which conformingly overlies the face of a doorknob and blocks the keyhole so that the required key cannot be used. The shield is protectively connected to the clevis or shackle of a padlock by links in such a manner that the legs of the shackle straddle the neck of the knob and accessibly support the key controlled lock.

This invention relates to a safety-type keyhole guard, that is, a readily attachable and detachable device which lends itself to reliable use, whenever necessary or desired, on a conventional-type lockable doorknob which is such in adaptability that its use minimizes the likelihood of an unauthorized person gaining entrance by way of a doorway to an apartment, quarters in a motel, a hotel room or, generally speaking, to ones private dwellingy or the like.

Briefly, and as will be hereinafter clarified, the doorknob can be any type whose front face has a keyhole slot and whose rear side has the usual reduced neck. The padlock is a well-known bicycle type characterized by a clevis-type shackle whose legs straddle the neck and are retained in a given position -by a key controlled Yale lock. The plate part of the readily applicable keyhole guard is provided with lateral positioning lugs which, in turn, are provided with eyebolts which link the lugs to coacting component parts of the shackle.

The inventive concept has to do (l) with the doorknob in combination with the above keyhole guard considered as a ready-to-use attachment and (2) the novel attachment by itself, and is to be construed accordingly. In either solution of the problem the key which controls the padlock is an essential aspect of the overall invention. An equally important aspect of this resourceful achievement has to do with the capability of using the unique guard not only as a safeguard to cope with unauthorized entry by way of an outdoor knob, it can be adapted to cover the turnable latch button on an inside knob as well as for indoor knobs for bathrooms and in many other ways, as will be hereinafter set forth.

This invention lends itself to feasible use by persons who own or rent apartments and may be leaving town for one reason or another and who may be anxiously concerned for the reason that duplicate keys may be accidentally in the hands of previous tenants, real estate agents or other persons. By the same token the invention is adapted for use by contractors and others owning temporary cn-the-spot offices, sheds, tool chests and the like at a construction site and for many and various other purposes.

ln carrying out the principles of the invention it should be understood that in the sense that the subject matter pertains to a ready-to-use attachment, the padlock may be construed as a part of the attachment or, alternatively, the attachment may be deemed to be directed to the platetype shield, the circumferentially spaced lugs on the marginal portion thereof and the eye-equipped links wherein the eyes at the ends thereof have a capability of connection with component portions of the padlocks shackle.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, -wherein like numerals refer to like parts throughout, and in which:

FIG. 1 is a front elevational view of the novel doorknob keyhole guard or attachment constructed in accordance with the principles of the invention.

FIG. 2 is a view on a slightly enlarged scale taken on the plane of the section line 2-2 of FIG. 1.

FIG. 3 is a view in perspective of the essential components of the attachment showing a slight modification in the aforementioned marginally connected lugs.

By way of introduction to the views of the drawing, it is to be pointed out that while the means shown in FIG. 3 represents the essence of the attachment aspect of the invention and also shows a slight modification, it is basically the same as corresponding parts appearing in FIGS. l and 2 for which reason it is thought that it will simplify the description to employ like numerals for like parts throughout the several views.

From a combination standpoint, the doorknob is a well-known type which is used indoors and outdoors but primarily outdoors and it is denoted in phantom lines, generally speaking, by the numeral 4. It comprises an enlarged head 6 and a reduced neck 8. The face of the head in practice is provided (not detailed) with a keyhole or, more specifically, a keyhole slot. It is within the purview of the invention to construe the concept as an attachment type keyhole guard and doorknob or as an improved self-contained and ready-to-use keyhole guard. The essential means of the keyhole guard is denoted, generally indicated, by the numeral 10. This means 10 is used in conjunction with an old but equally important device which is here shown as a conventional bicycle type padlock 12.

Taking up particularly the means 10, this comprises a concavo-convex disk-like imperforate metal plate 14 which is of a size to cooperatively cover the keyhole in the head of the doorknob. This plate functions as a protective shield and -blocks access to the keyhole and prevents one from inserting a key whenever necessary or desired. The marginal edge portion of this guard plate or shield is provided with adapters which, more specifically, comprise laterally directed lugs 16 having laterally bent terminal ends 18. The lugs may be provided with slots 20 as shown in the adaptation in FIG. 3 or may be made without slots. The end portions of the lugs may be joined directly to the marginal edge 22 as at 24 or the points of attachment may be slightly inward of the marginal edge in the manner shown in FIG. 2. Each lug is provided with an eyeequipped link. Each link comprises a solid shank 26 having a headed end portion 28 and having an eye 30 at the opposite end. These shanks can slide and can also rotate relative to the apertured portion 18 of the coacting lug. The eyes are constructed for connection with component portions of the U-shaped clevis or shackle 32 of the aforementioned padlock 12. The shackle, as usual, has legs 34 which straddle the neck of the knob and the legs are provided with ratchet teeth 36. The thus toothed legs extend through component portions 38 of a ybarrel or cylinder type lock 40 constructed with turnable keyhole means 42 to accommodate a padlock key (not shown).

It is within the purview of the invention to make the lugs 16 bendable so that the user can adapt the same to doorknob heads of different :shapes and sizes. The free turning and slidable connection of the headed ends 28 of the Shanks 26 with the lugs also adds to the adaptable and flexible capability of the over-all guard. It follows that the guard lends itself to use with adaptability and eiciency on most doorknobs which are currently being used.

. Even though one may have the right key, it is possible to block use thereof when the attachment is being used. There are instances where managers and owners of hotels, apartments and motels find it necessary to apply the guard at a time when they wish the tenant to report to the front office before being able to enter the premises or room as the case may be. It is evident, however, that it is unnecessary to -attempt to cover all of the many ways in which the invention is capable of satisfactory use and inasmuch as the invention is thought to be clear from the preceding description and drawings, a more extended description is thought to be unnecessary.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modications vand changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described.

What is claimed as new is as follows:

1. In combination, a doorknob embodying a head provided in a front side with a keyhole and having a reduced neck on its rear side, a padlock embodying a U-shaped shackle having elongated legs straddling said neck and held partly by said head, a key controlled barrel-type lock bridging and lockably mounted on said legs, a keyhole guard overlying the face of said head and blocking said keyhole, and -means operatively connecting said guard with said legs, said guard comprising a shield, said guard connecting means comprising links connected to the legs of lsaid shackle, and lugs on said shield to which said links are connected.

2.. A self-contained ready-to-nse keyhole guard for attachment to a doorknob having a head and neck and wherein the head is provided with a keyhole, said attachment comprising a plate adapted to overlie the keyhole, said plate having means bordering its marginal edge and designed and adapted to be detachably joined to a padlock, the means bordering the -marginal edge of the plate comprising a plurality of circumferentially spaced laterally projecting lugs which have corresponding ends integral with said marginal edge and have their other ends free and apertured, each apertured end being provided with a headed shank which is freely rotatable and slidable, said shank -being provided at one end with an eye, said eye being adapted to embrace a predetermined component part of the shackle of a bicycle-type padlock.

3. In combination, a doorknob embodying a head having a front face provided with a keyhole and having a reduced neck on a rear side, a padlock embodying a U- shaped shackle having elongated legs straddling said neck and held in a given position partly by said head, a key controlled barrel-type lock bridging and lockably mounted on said legs, a keyhole guard comprising a plate constituting a shield, said plate being of a diameter larger than the diameter of said head and being :shaped and contoured to span and conformingly covering the face of said head in a manner to block and render said keyhole inaccessible, and means for operatively connecting said plate with said legs, said means embodying a plurality of laterally directed lugs having outer ends integrally joined to marginal circumferentially spaced portions of said plate, and a plurality of complemental links which are designed and adapted to coact with :said lugs and legs, respectively.

4. The combination defined in and according to claim 3, and wherein said links have headed ends operatively joined to cooperating end portions of said lugs and have eye-equipped ends which are joined to coacting portions of the respectively cooperable legs of said shackle.

References Cited UNITED STATES PATENTS 2,463,195 3/ 1949 Mungan 70-416 2,610,877 9/1952 Weaver 292-1 2,883,850 4/1959 Falck 70-431 3,167,945 2/ 1965 Gookman 70-428 3,245,240 4/ 1966 De Forrest 704416 X 3,343,387 9/ 1967 Cochran 70-424 MARVIN A. CHAMPION, Primary Examiner ROBERT L. WOLFE, Assistant Examiner U.S. Cl. X.R. -209 

